A single water molecule (HOH) is held together by
A) a single covalent bond.
B) a double covalent bond.
C) two polar covalent bonds.
D) hydrogen bonds.
Which of the following hormones causes glucose release and, consequently, a rise in the
concentration of sugar in the blood?
A) insulin
B) glucagon
C) calcitonin
D) oxytocin
If the aqueous humor circulates but does not drain properly, the likely result will be the
development of
A) glaucoma.
B) myopia.
C) astigmatism.
D) hyperopia.
Humans share several features with salamanders. Certain genes and proteins are nearly
identical between the two species; both species have four limbs with a similar skeletal
structure; the species’ early embryos are very similar; and where the salamander has a
functional tail, humans have a vestigial tailbone. In evolutionary terms, these are
examples of
A) geographic similarity.
B) homology.
C) adaptation by natural selection.
D) coincidental similarity.
Much of the intracellular structure of a eukaryote cell is involved in protein synthesis.
The figure shows the amounts of protein in cells at different parts of the cell cycle
between two cell divisions. G1 is a stage just after the cell has divided, and G2 is the
stage just before the cell divides again. S is a stage when the cell is synthesizing
material such as DNA, mitochondria, and other organelles.
Which of these conclusions cannot reasonably be drawn from the graph?
A) Protein production occurs throughout the cell cycle.
B) Increase in ribosomal activity occurs as a cell prepares to divide.
C) Cells export a large amount of protein following cell division.
D) There is always a supply of amino acids in the cell.
Carnivorousness in plants is primarily an adaptation for
A) growing in soil poor in organic material.
B) growing in soil poor in usable nitrogen.
C) obtaining supplemental carbon for photosynthesis.
D) discouraging herbivorous insects.
Refer to the figure above. As an adult, if you had to choose only one of these two foods
(corn or beans) to provide you with essential amino acids, which would you choose?
A) corn, because it provides more essential amino acids than beans
B) beans, because they provide more essential amino acids than corn
C) Both are choices of the same value because they provide histidine.
D) corn, because it grows more successfully than beans
An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How
many electrons does boron have?
A) 11
B) 15
C) 5
D) 2
Which of the following essential nutrients is most likely to leach from the soil?
A) Ca2+
B) Mg2+
C) K+
D) NO3
–
Which of the following molecules is a product of photosynthesis?
A) CO2 and chlorophyll
B) glucose and O2
C) O2 and CO2
D) glucose and CO2
Which of the following statements regarding viral diseases is false?
A) RNA viruses tend to have an unusually high rate of mutation because their RNA
genomes cannot be corrected by proofreading.
B) New viral diseases often emerge when a virus infects a new host species.
C) Very few new human diseases have originated in other animals because the genetic
differences are too great.
D) AIDS was around for decades before becoming a widespread epidemic.
An airfoil provides lift because air moving over a wing must travel
A) a greater distance than air moving under the wing, creating a lower pressure system
above the wing.
B) a greater distance than air moving under the wing, creating a higher pressure system
above the wing.
C) a lesser distance than air moving under the wing, creating a lower pressure system
above the wing.
D) a lesser distance than air moving under the wing, creating a higher pressure system
above the wing.
Which of the following generates the ATP that is required for movement of the sperm’s
tail?
A) a mitochondrion in the neck and middle piece
B) mitochondria in the sperm tail
C) the sperm plasma membrane
D) the acrosome
The active site of an enzyme is
A) the region of a substrate that is changed by an enzyme.
B) the highly changeable portion of an enzyme that adapts to fit the substrates of
various reactions.
C) the region of an enzyme that attaches to a substrate.
D) the region of a product that detaches from the enzyme.
The production of estrogen and progesterone is drastically decreased in women
experiencing menopause. This can cause women to experience poor sleep, night sweats,
thinning of bones, and brief moments of feeling hot. What is another biological effect of
low amounts of these hormones in women?
A) being no longer able to maintain normal nerve cell development
B) being no longer able to reproduce successfully
C) being likely to become anemic
D) being likely to experience joint swelling
Assuming that the probability of having a female child is 50% and the probability of
having a male child is also 50%, what is the probability that a couple’s first-born child
will be female and that their second-born child will be male?
A) 20%
B) 25%
C) 50%
D) 75%
Plants are sometimes used for phytoremediation in areas where the soil has been
contaminated with heavy metals. Suppose the Acme Remediation Company is
proposing to remediate a contaminated area that you wish to restore. Acme presents you
with the following data as evidence of their company’s ability to remediate soil.
What likely caused the loss of metals in the control soil?
A) being washed away by water draining through the soil
B) evaporation of the metal molecules into the air
C) absorption of the metal molecules by clay particles
D) buildup of humus
Which of the following occurs during cellular migration and development into
specialized tissue?
A) Cells are transferred to the appropriate region of the embryo via the bloodstream.
B) Cells fuse to produce multinucleated giant cells.
C) Similar cells glue themselves in place by secreting glycoproteins.
D) Most cells of the developing tissue undergo the process of apoptosis.
Which of the following hormones affects the greatest variety of cell types?
A) parathyroid hormone
B) melatonin
C) growth hormone
D) calcitonin
Enhancers are
A) adjacent to the gene that they regulate.
B) required to turn on gene expression when transcription factors are in short supply.
C) DNA sequences to which activator proteins bind.
D) required to facilitate the binding of DNA polymerases.
Uplift and formation of a mountain range divide a freshwater snail species into two
isolated populations. Erosion eventually lowers the mountain range and brings the two
populations together again, but when they mate, the resulting hybrids all produce sterile
young. This scenario is an example of
A) sympatric speciation.
B) allopatric speciation.
C) incomplete speciation.
D) diversifying speciation.
Which of the following has been a major source of ozone destruction over the past 50
years?
A) chlorofluorocarbons (CFCs)
B) ethylene glycol (C2H6O2)
C) carbon dioxide (CO2)
D) methane (CH4)
Peptide bonds
A) are used to form amino acids.
B) form between fatty acids.
C) are formed by a hydrolysis reaction.
D) link amino acids.
In examining the effects of atrazine, one of the most commonly used herbicides in the
world, scientists studied the mating behavior of male frogs exposed to atrazine (Atr)
compared to a group that was not exposed (Non). The results are shown in the figure.
Part B indicates that
A) atrazine is an endocrine disrupter.
B) trazine-treated males are more successful in mating than nontreated males.
C) there were fewer atrazine-treated males than nontreated males.
D) atrazine males are unable to mate.
Which of the following treatments could possibly help to transform the bone on the
right to the bone on the left?
A) wearing long sleeves while out in the sun
B) swimming for 30 minutes a day
C) removing calcium from the diet
D) taking vitamin D supplements
Which of the following would prevent an organism from becoming part of the fossil
record when it dies?
A) It is fully decomposed by bacteria and fungi.
B) It is buried in fine sediments at the bottom of a lake.
C) It gets trapped in sap.
D) It is frozen in ice.
Cows can derive nutrients from cellulose because
A) they produce the enzymes that break down cellulose.
B) they chew their food so thoroughly that cellulose fibers are broken down.
C) their intestinal tract contains cellulose-hydrolyzing microorganisms.
D) they convert cellulose into starch, which is easily broken down in the intestinal tract.
Which part of this figure represents the anther?
A) structure A
B) structure B
C) structure C
D) structure D
Smooth endoplasmic reticulum
A) stores calcium ions in muscle cells.
B) is the major site of carbohydrate synthesis in eukaryotic cells.
C) produces proteins for cell membranes.
D) helps assemble ribosomes for protein synthesis.
Consider a stable frog population living at carrying capacity in a pond. If an average
female produces 6,000 eggs during her lifetime and an average of 300 tadpoles hatch
from these eggs, how many of these tadpoles will, on average, survive to reproduce?
A) 0
B) 2
C) 10 to 20
D) more than 100
According to the figure above, which amino acid is found in corn but not in beans?
A) methionine
B) valine
C) threonine
D) lysine